Error during running the demo

[phtruongan]

when I try to run demo_showcandidates.py:
import segment
ImportError: /usr/lib/x86_64-linux-gnu/libboost_python-py34.so.1.55.0 Undefined symbol: PyUnicode_As...

I don't know why because I have installed boost 1.59.0 for python.
If I remove the package libboost-all-dev (1.55.0): the segment return another error liboost_python-py27.so,1.55.0: No such file or directory.

I hope you can help me about that error.
Thank you so much.